Method and apparatus used in producing staves



J. EVANS 3,062,251

METHOD AND APPARATUS USED IN PRODUCING STAVES 4 Sheets-Sheet l ATTORNEYS Nov. 6, 1962 Filed Dec. 29, 1958 METHOD AND APPARATUS USED IN PRODUCING STAVES Filed Dec. 29, 1958 J. EVANS Nov. 6, 1962 4 Sheets-Sheet. 2

V ATTORNEY 5 METHOD AND APPARATUS USED IN PRODUCING STAVES Filed Dec. 29, 1958 J. EVANS Nov. 6, 1962 4 Sheets-Sheet 3 s M A J m U Q Q f w W A g, @Q f g M M a I. i 2 7 5 A 3 A X M Q whllm SQ Q kw QAN km METHOD AND APPARATUS USED IN PRODUCING STAVES Filed Dec. 29, 1958 J. EVANS Nov. 6, 1962 4 Sheets-Sheet 4 H WINE/M M INVENTOR J/M [VA/v6 wwyw ATTORNEY 5 United States Patent 3,062,251 METHOD AND APPARATUS USEDIN PRODUCING STAVES Jim Evans, Hot Springs, Ark. Filed Dec. 29, 1958, Ser. No. 783,334

6 Claims, (Cl. 147-19) This invention relates to coopering and involves method and apparatus used in the process of manufacturing unfinished wooden staves, and is more particularly related to an automatic stave bolt equalizeL,

In the process of manufacturing staves, a hardwood tree, usually white oak, is cut in random lengths of roughly 40 inches, depending upon the size of Wooden barrels for which the staves are being manufactured. Each length of log is split lengthwise into what are termed stave bolts which have no specific regularity in size (length) or cross-section (shape), although the bolts preferably are pie shaped or quarters of approximate 40" of logs. The irregular sized and shaped stave bolts must first be cut and sized to standard lengths, such as a conventional 36 inches. To cut. and size irregular sized and shaped stave bolts is called the equalizing process and is the first step in the manufacturing of barrel staves from stave bolts. The second step in the manufacturing process is to cut the sized stave bolts lengthwise by a barrel saw into rough or unfinished barrel staves in order to obtain the lengthwise curvatureof a barrel. The last step would be for the rough staves to be edged to eliminate waste prior to final processing by the cooperage shop into barrels.

This invention primarily concerns the first stage in such manufacturing process although it also envisages and enables an assembly line procedure almost fully automated for the complete rough finish process. Except for the use of twin rotary saws, usually powered by a line shaft and flat belt, all prior known machines and methods of stave bolt equalizing, are manually operated. To a large extent, a manually operated stave bolt equalizer generally resembles the antiquated manual loom and does not contribute to assembly'line volume production of barrel staves. Under present day standards previously known stave bolt equalizers, utilizing a large amount of manual steps in manipulation of the bolt during equalization, have resulted in continually rising production costs with disproportionate and insignificant increase in output volume.

The problems inherent in the manually operated stave bolt equalizer are apparent in the following brief description of such manual operations. alternate in (1) picking up stave bolts weighing about 80 pounds each from a stack, (2) placing a bolt one at a time on a manually operated sliding bolt carriage or rack, (3) shove the rack (and bolt) between twin rotary saws which cut the ends of and thus size the bolt, (4) pull the sized bolt and rack manually back to the starting position, (5) lift the cut and sized stave bolt from the rack, and (6) turn and place-the cut and sized stave bolt on a reserve table. As the supply of cut and sized stave bolts accumulates on the reserve table, the operator of the'manually operated stave bolt equalizer must shove up to 8 stave bolts to the end of the reserve table as a supply for the operators of the barrel saw which as has been noted cuts and shapes the stave bolts into rough barrel staves.

The use of themanually operated stave' bolt equalizer Generally, two men is that the operators are exposed to the open cutting stave mill industry because no stave bolt equalizing machine or method has previously been devised to overcome the apparent obstacle created by the irregularity in size and shape of stave bolts.

This obstacle of irregularity in shape prevented (1) the aligning of stave bolts for a square cut by the saws, (2) the feeding of stave bolts in a steady flow to the saw without danger to the operators, (3) the conveyance of stave bolts in a unidirectional fiow through the equalizer to the barrel saw operators and (4) the utilizing of a direct assembly line method of producing rough finished barrel staves.

The present invention overcomes the aforedescribed problems by providinga chain type conveyor with steel or iron dogs attached to conveyor chains to engage and compel the stave bolts to pass through the twin rotary saws to the reserve table and conveyor, coordinated with a yielding hold-down mechanism to apply force on and maintain the bolts snug against the conveyor and against the dogs regardless of irregularity in size. These coordinated forces compel the alignment of the stave bolts as they start and pass through the twin rotary saws during, 1 the sawing process. The chain conveyor system permits .7 the use of shielding structure between the operator and the twin rotary saws. The chains of the conveyor are powered by an electric motor, independent from the saw power device, have steel dogs attached at appropriate intervals and revolve on sprockets in a through conveyor frame situated between the twin rotary saws. The chain conveyor system provides the power to carry the stave bolts to, through and from the saws and to move the cut stave bolt off the equalizer where a further conveyor can carry' the equalized bolts to the operators of the barrel saw without the necessity of the equalizer operator physically handling the cut and sized stave bolts.

Accordingly, a primary object of the present invention I resides in a novel automatic equalizer which confines movement of and conveys stave bolts through twin power- 1 operated rotary saws in the equalizing process. It is an associated object to convey such bolts by means of a power operated chain conveyor system, onto a reserve table and further conveyor and thus on to the next step in the manufacturing'process of barrel staves.

Another object resides in providing a straight through power operated chain conveyor system in novel structural and functional cooperation with a hold-down device, eliminating any necessity for the machine operator to go between the twin parallel cutting devices which are preferably rotary saws.

Still another object resides in providing a novel equalgravity hold-down mechanism to align, confine movement of, and guide the stave bolts into the twin rotary saws,

while the stave boltsare on the chain conveyor, for cutting and sizing and holding the stave bolts firm and in place during the cutting process.

Also an object of the invention is to provide a novel, method of automatically feeding stave: bolts into an equal- 1 izer and deliver them, cut to proper length, to the barrel saw operator.

A still further object residesin the provision of, a novel simplified, assembly line production of barrel staves.

through the use of an automatic stave bolt equalizer.

Further novel features and other objects of this invention will become apparent from the following detailed Patented Nov. 6, 1952 description, discussion and the appended claims taken in conjunction with the accompanying drawings, showing a preferred structure and embodiment, in which:

FIGURE 1 is a schematic diagram illustrating an assembly line disposition of stave mill machines used in the process of manufacturing rough barrel staves, made possible by the equalizer of, and thus being in accord with, the present invention;

FIGURE 1A is a diagrammatic cross section taken on line 1A1A in FIGURE 1 and illustrates the conveyor placed under the flooring of the stave mill;

FIGURE 2 is a schematic diagram illustrating the disposition of previously known stave mill machines used in the process of manufacturing rough barrel staves in accord with prior art teachings;

FIGURE 3 is a partially broken away, side elevation of a stave bolt equalizer constructed in accord with this invention;

FIGURE 4 is a plan view of the stave bolt equalizer illustrated in FIGURE 3 with only one of the conveyor chains shown;

FIGURE 5 is a vertical section through the stave bolt equalizer taken on line 55 of FIGURE 3, illustrating the lateral disposition of the equalizer saws, the conveyor races and the hold down rails;

FIGURE 6 is an enlarged side elevation view of the hold down mechanism including its suspension linkage;

FIGURE 7 is a detail section view taken on line 77 of FIGURE 6 illustrating the structural cooperation between the hold-down hangers and the overhead holddown brace device;

FIGURE 8 is a detail view of the guide structure between a hold-down hanger and the hold-down support frame;

FIGURE 9 is a detail view of the structural cooperation between a vertical yoke leg and horizontal cross braces of the hold-down support frame also identical to the cross braces of the conveyor table; and

FIGURE 10 is a detail illustration of one of the stave bolt abutment dogs welded to the conveyor chain.

The specific construction and method of stave bolt support assembly, FIGURE 3, can be adjusted vertically equalization utilized in the stave bolt equalizer 20 will be first described, with reference to FIGURES 3-10. Thereafter, a comparison of the previously used process of manufacturing rough finished staves will be made with a procedure now possible by using the equalizer of the present invention. Like reference characters identify the same parts in different views of the drawing. A component designated by a reference character with a prime mark aflixed thereto is a substantial duplicate of the component designated by the same reference character without a prime mark afiixed thereto.

FIGURES 3, 4, and 5 illustrate an exemplary stave bolt equalizer 20, in accord with this invention, consisting basically of three structurally and functionally combined components, a conveyor assembly 22, a stave bolt holddown assembly 24 and a twin rotary saw assembly 26, all being supported by base structure consisting of a front and rear yoke 28 and 30. The machine is capable of quick disassembly into several components for ease in portability.

Each of the front and rear yokes 28 and 30 have the same components, hence only one yoke 28 will be described and identical components of the other yoke 30 will be identified by the same reference numerals with primes afiixed. Yoke 28 has two laterally spaced, up right legs 32 which can be made as shown, from two channel beams 33 placed back to back in slightly spaced relation providing a vertical slot 34 in each leg. The two channel beams 33 are secured at their bottom ends to a common plate 36, as by welding. At the upper end of slot 34 a small filler bar 38 connects and secures the two beams 33, as by welding. Each yoke 28 and 30 is completed by upper and lower vertically s'hiftable cross braces 40 and 42 which also, respectively, constitute portions of between wheels 68 and82.

78 of sprockets 82 canbe adjusted vertically on bracketsv along the legs relative to the ground level and/ or to each other. It is clear that the lateral spacing of the two legs 32 of each of front and rear yokes 28 and 30 will be greater than the random lengths of stave bolts which will be disposed horizontally as they are passed in a lateral fashion between the yoke legs'by the conveyor.

Conveyor assembly 22. is arranged in the manner of an elongate horizontal frame consisting of the support table 46 a chain conveyor system and its drive, as will be described, and the table 46 also serves as a support base for the twin rotary saw assembly 26.

Table 46 is basically a planar frame with side members consisting of two long channel beams'50 and 50" arranged horizontally and disposed sideways on top of the aforedescribed lower cross braces 42 and 42. Each cross brace 42 is a fabricated construction consisting of two lateral channel beams 52 and 54, spaced slightly from each other, back to back and rigidly secured, as by welding, to the lower'flange of the longitudinal side beams 50 with both cross brace ends projecting laterally below side beams 50. Cross brace beam 54 is somewhat shorter than its mated beam 52 and disposed with its ends within the inside channels of a pair of yoke legs 32. The longer cross brace beam 52 has its opposite ends disposed outside of and engaging the outer flange surfaces of the two channels 33 of associated legs 32 as can be clearly seen in FIGURE 4. The front and rear cross braces 42 and 42 of the conveyor table 46 can thus slide up and down on yoke legs 32 as desired for height adjustment and are secured in desired position by tightening bolt assemblies 48.

The longitudinal beams 50 and cross braces 42 of table 46 provide a rigid essentially box like frame supported between thefront and rear yokes 28 and 38 and projecting a considerable distance in front of and to the rear of the yoke assemblies. On the upper flange of each of the longitudinal side beams 50, a pillow block bearing 58 is bolted adjacent the front end, and a second pillow block bearing 60 is bolted adjacent the rear end. Disposed laterally across the front end of beams '50 and rotatably journalled in pillow block bearings 58 is a sprocket wheel shaft 62 which has two spaced apart sprocket wheels 64 non-rotatably secured thereto between the two beams 50. A somewhat similar shaft 66 is rotatably journalled in the rear pillow block bearings 66" and non-rotatably carries two sprocket wheels 68 in longitudinal alignment with front sprocket Wheels 64. Rear shaft 66 has one end 70 projected beyond the side beam 50 upon which is non-rotatably secured'a pulley wheel or sheave 72 (FIGURE 4), for a purpose to be explained hereinafter.

Shown at the left hand portion of FIGURE 3 is a depending bracket 76 which can be made from short pieces of channel iron rigidly secured to the lower flanges of side beams 50. One such bracket 76 is secured under the front end of each beam 50 and each bracket mounts a pillow block bearing 78 which rotatably journals a .third shaft 80.. Non-rotatably carried on shaft 80 are Each aligned set of three sprocket wheels 64, 68 and I 82 is engaged byan endless roller link chain 84 of sufiicient'length to provide slight slack in the lower stretch The pillow block bearings 76 to provide desired slack in the chain. Between each set of front and rear sprocket wheels 64 and 63 is a channel shaped link chain race 86, its bottom surface being essentially tangential to the root circle of the front and rear sprocket teeth (see FIGURE 3). The upper stretch of each endless chain 84' lies within its associated race 86 between the front and rear sprocket wheels 64 and 63, and the side flanges of channel race 86 project slightly above the chain and provide tracks which carry the weight of the stave bolts and serve to oppose the forces exerted on the stave bolts by the hold-down assembly. Eachchain race 86 is secured in position by a plurality of plates 88 welded to the outside of the race channel 86 and to the inside of the table side beams 5%.

Shown in FIGURE 3 and more clearly in FIGURE 4, auxiliary table extension plates 90' and 2% are secured essentially parallel with the upper surface of the chain races 86. Extension plates 91 are supported on the front ends of table beams Sil by short channel beams 92 and 94, the assembly being Welded into a rigid unit. Additional small brace plates 96, 97 and 98 constitute a strength frame secured as by welding under each plate 90 and tie it in with the side flanges of the associated chain race 86. Note in FIGURE 4, a cutout is located in each extension plate 90 just above and adjacent to the outer surface of each sprocket wheel 64. This permits clearance for stave bolt driving dogs 102 which are Welded on the outer side links of each chain 84, as will be later described. These extension plates serve as short receiving platforms upon which the machine operatorcan place one or more stave bolts and slide them onto the conveyor chain races. In addition they serve as safety shields over the chain front end sprockets 6'4.

Shown in FIGURE 4 adjacent the rear end and to one side of table 46 is a platform 106 which supports an electric motor 1438 having a gear reduction attachment 110 from which is projected a drive shaft 112 disposed parallel to sprocket wheel shaft 66. Non-rotatably secured to drive shaft 112 is a pulley wheel or sheave 114 in drive belt alignment With the pulley wheel 72 on the projected end 70 of sprocket wheel shaft 66. Belts 116 (two being illustrated) are drive connected between pulleys 114 and 72. Operation of electric motor M38 will cause rotation of shaft 66 and enable correlated movement of the two endless conveyor chains 84 which will be pulled along the chain races 86 by rear sprocket wheels 68. It is to be understood that the pulley sheaves can be single or multiple if desired. In actual practice the double belt drive has proven more satisfactory than a single belt drive using a conventional /2 horsepower electric motor and a reduction gear drive, and if plural stave bolts are being cut a triple belt drive might be desired to reduce the tendency of slipping.

The drive dogs 102, previously referred to, are preferalby- /r" steel plates shaped like a right triangle as shown in FIGURE 10. Each conveyor chain 34 has a plurality of these dogs 102 welded to a link piece on the outside of the chain and project approximately 4.5 inches above the chain. The leading edge of each dog 102 is substantially normal to the path of the associated chain and the dogs 102 are disposed in lateral pairs. In the disclosed embodiment, the chain conveyor includes four pairs of such dogs spaced at intervals of approximately five (5) feet. It is thus clear that upon operation of the motor 108 the conveyor chains 84 will start' on their endless path and when a stave bolt is placed on table extensions 90 and pushed onto the chain races 86 a pair of dogs 102 will engage the stave bolt and positively force it in lateral disposition sideways along the races 86 and through the support yokes 28 and 30 and off of the rear end of the table 46.

Saw assembly 26 consists of twin rotary saws 12$) and 120'powered'by an electric motor 122 (FIGURE 4) through a multiple V-belt drive. In the exemplary embodiment the saws 12%, 120' are 48 inch diameter and motor 122 has a horsepower rating. The twin saws beyond the table side beams 50 and the shaft 124 passes below the conveyor chain races 86'. Non-rotatably secured to shaft 124 between the bearings 126 is a mul-. tiple sheave V-belt pulley 128- (six sheaves as disclosed).

To the rear of the rear yoke 30 a line shaft 130 is rotat ably journalled in pillow block bearings 132 secured on the top flanges of side beams 50, and non-rotatably carries a multiple sheave V-belt pulley 134 (six sheaves) between the bearings and aligned with pulley sheave 128. Six V-belts 136 drive connect the two pulleys 128 and 134. One end 138 of the line shaft projects through its associated bearing 132 and is connected through a flexible drive coupling 140 to the armature shaft 142 of motor 122. The dimension between saw blades 120 and 12% in the exemplary embodiment is 36 inches, a standarcl length for rough finished barrel staves. Motor 122 is mounted on and supported by a platform 144 which can be secured to the rear cross beam 42 and can be additionally braced by a supporting frame 146. Blocks 148 can be used between frame 146 and the ground to provide for variations in vertical height of the motor platform 144 and support frame 146 when the height of conveyor table 46 is changed.

It is to be understood that the saw diameter, distance between saws and the motor rating can be varied depending upon the sizes of stave bolts and the desired lengths of the rough finished staves.

The hold-down assembly 24 is used to provide a force holding the stave bolts against the races and the conveyor drive dogs. Due to the rough and uneven nature of stave bolts, the hold-down assembly must have a considerable degree of flexibility during its effective opcrating positions. To provide this flexibility, the hold down assembly '24 is made as two substantially independent units 152 and 154. Because these two units are identical, only one will be described in detail.

One of the hold down units 152 is suspendedover and in vertical alignment with one conveyor chain race 86 and the other unit 154 is in similar disposition over the other parallel chain race 86. Each unit 152 and 154 has a hold down slide or runner 160, which is made from a T-section beam, suspended by two vertical arms 162 and 164. The two arms 162 and 164 ofeach unit are disposed adjacent the inner side of an associated saw 120 and as seen in side profile (FIGURE 3), to the front and rear of the saw blade. The T-section slide runners are disposed with the central flange 166 upright and the lower ends 168 of the vertical arms 162 are forked and are pivotally connected by bolts 170 to the upright central flange 166 oftheir respective runners 160. Just ahead of the front pivotal connection bolt 170, the central flange 166 of each runner 160 has been removed, leaving only the cross flange 172 V which is bent to incline upward at an approximately 30 degree angle to the horizontal. The bent up forward portions 172 of runners 160 serve as guide abutments for stave bolts being conveyed under the hold down runners 160 into the saws 120.

The upwardly extending arms 162 and 164 of each of the hold down units 152 and 154 are suspended from the aforementioned. hold down support assemblies 44in r a manner limiting the lowermost disposition ofgrunners 160 to several inches above their associatedchain races 86 and to provide clearance abovethe dogs 102 but permitting vertical shift of the arms above the lower limit. Each hold down unit 152, 154 has its own hold-l down support assembly 44 which includes four angle beams 174, 175, 176 and 177. All of the angle beams 174177 (see FIGURE are disposed to extend between the fore and aft upper cross braces 40 and 40. Two of the beams 174 and 175 rest on top of cross braces 40, 40' and are secured by welding thereto. The upright flanges of the two beams 174 and 175 are disposed facing each other and spaced apart to provide a longitudinal slot, aligned vertically above the associated chain race 86, of sufiicient width to provide a confining but free aligning fit for the flat bar shaped vertical runner arms 162 and 164. The remaining two angle beams 176 and 177 are secured by welding to the underside of the upper cross braces 40, 40 immediately below the beams 174 and 175 to thus also provide a longitudinal slot below and vertically aligned with the slot between the upper beams.

Both of the vertical arms 162 and 164 of a hold-down unit 152 or 154 pass upwardly between beams 176 and 177 and through the slot between beams 174 and 175. Small side plates 180, bolted to the upper ends of arms 162 and 164, serve as lower position limit stops in abutment against the flange edges of the two upper beams 174 and 175. Removal of these plates 180 will permit removal of the hold down units 152 or 154. Vertical disposition of arms 162 and 164 between the upper set of angle beams 174 and 175 and between the lower set of angle beams 176 and 177 effectively stabilizes the runner unit against swinging sideways. The upright arms 162 and 164 are maintained in proper longitudinal disposition relative to cross braces 40 by stop devices secured in the slot between the top two beams 174 and 175 in front and rear of each arm 162 and 164. Such stop devices can be simple welded blocks or plain bolts however, as shown, it is preferred that each device consist of a roller 182 (FIGURE 8) journalled on a bolt 184 disposed laterally through the upright flanges of upper beams 174 and 175. The rollers 182 should be spaced apart a slightly greater distance than the width of anarm 162 to permit some play as the associated hold down unit 152 rises and falls when a stave bolt is forced under the runner 160. Roller units are not necessary or desirable on the lower beams 176.

The aforedescribed suspension of each hold down unit 152 and 154 will permit the front end of the runner 160 to riase and/or lower ahead of the rear end in a simplified 'manner which effectively prevents binding and assures that an effective downwardly directed force is maintained on the stave bolt passing below the runners and, due to the independent suspension of each slide runner unit, both ends of a stave bolt will be subjected to essentially equal downwardly directed forces regardless of the uneven and rough nature of the, stave bolts.

.The weight of the hold down runner units 152 and 154, constructed as proportioned in the exemplary disclosure, will be approximately 135 pounds. It should not be less than 100 pounds which is the approximate force necessary to keep the stave bolts aligned on the chain conveyor 22 as the bolts go through the saws 120 and to hold the stave bolts firmly for even cuts on each end. If desired, auxiliary springs 188 connected between the beams 174 or 175 and vertical arms 162 and 164 '(one being shown in FIGURE 5) can be utilized to supplement the force due to gravity on the hold down runners. As a cut stave bolt passes beyond the cutting edges of the saws 120 and is conveyed on between the saws, the hold down mechanism 24 continues to apply a force holding the stave bolt in place on the chain conveyor 22 as it moves and, toa degree, protects the saws 120 from damage which could otherwise result from possible side skewing of free flowing stave bolts. Inasmuch as the chain conveyor dogs 102 are 5" apart on the chains 84, several stave bolts, preferably not more than two, can be placed on the chain conveyor between the dogs. Without the hold down mechanism 24, the stave bolts, being irregular in size and shape,

could easily change position on the conveyor as the bolts approach the cutting edges of the saws. The links of chains and the shape of the bolts allow some movement of the bolts on the conveyor, and the rotary saws create another force during cutting of the bolts which is counteracted by the hold down mechanism. Thus, the different forces become balanced to permit a smooth flow. As is apparent, the chain dogs 102 in cooperation with the runners 160 of the hold down mechanism have the tendency to cause the stave bolts to come into contact with the twin rotary saws at the same time. Another beneficial effect is to place the same pressure on each of the twin saws as the bolts are cut or commencing to be cut, eliminating, to a degree, unequal strain on the shaft 124 which carries the twin saws 120.

On the horizontal hold down supports 44, through which the vertical arms 162 and 164 of the hold down mechanism can move up and down, the rollers 182 on'each side of the vertical arms permit the vertical arms to go up and down with the least amount of friction. The forked ends 168 of vertical arms 162 and 164 are attached to the runners in a pivotal manner so that the front of the hold down mechanism can raise while the rear is in the lower position and vice versa. The aforementioned roller bearings 182 in the overhead supports 44 also prevent the hold down mechanism from sliding to the rear of the support beams, as a stave bolt slides under the runners 160.

Safety shields 194 (FIGURE 3) can be secured to the I sides of legs 32 of the front and rear yokes 28 and 30 of the base structure, to prevent the operator from coming near the twin rotary saws and to reinforce the base structure. These shields 194 can be metal plate, plywood or heavy steel mesh screen. The conveyor table 46 being adjustable up or down within the yokes 28 and 30 of the base structure, can provide alignment as to height between the stave bolt equalizer 20 and a reserve table conveyor 200, FIGURE 1 which receives stave bolts from the equalizer 20 and feeds stave bolts to the barrel saw op.- erator.

Preferably, the conveyor electric motor 108 and the saw electric motor 122 are controlled by separate switches and 192 mounted in a convenient location to the operator,

as on cross piece 94 at the front of the machine (see FIGURE 4).

Additional V belts from the electric motor to the con-' veyor may be added to reduce slippage. The chains in the conveyor are flat link chains and may be varied in size according to the size of sprockets used. The saws and to successful utilization of the invention. The machine made as illustrated weighs approximately one ton.

Operation of Stave Bolt Equalizer The operator of the machine, after turning the respective motors 108 and 122 on by switches 190 and 192, performs only one manual operation in placing stave bolts 7 on the conveyor table extensions bars 90 and moving them to a position just beyond the front sprockets 64 of the twin chain conveyor. The next pair of chain dogs 102 then engages the sides of and forces the stave bolt through the twin saws 120 to the end of the conveyor table 46.

It makes little difference which side, i.e., the rough bark side or the split sides, of a stave bolt is placed on the chain races 86 or faces the dogs 102 since the operator during the initial placement of the stave bolts on the chain sees that the stave bolts are relatively firm against the dogs to prevent the stave bolts from changing position before the bolts come into contact with the hold-down mechanism and the saws. This'initial period of manual adjustment can be shortened, if desired by increasing the length of the lead portion 172 of the runners 160 on the bottom of the hold-down assembly 24.

Thusthe upwardly inclined portions '172 of the holddown runners 160 can engage a stave bolt at two lateral positions as it moves toward the saws. Independent mounting of the two runners assure that both will maintain engagement with a stave'bolt and, because of their weight and the'inclination of portion 172, initially create a force tending to oppose stave bolt movement toward the saws. This laterally spaced pair of force applications will dispose the stave bolt tightly against the two laterally disposed dogs 102 which irresistably then force the stave bolt under the two runners 160 causing upward, independent movement of the forward part of both runners. Because of the ability of the front and/or the rear of each runner to independently rise and fall depending upon the thickness of a stave bolt passing under the runner and further because of the independent suspension of each runner, spaced pairs of forces are always present to maintain the stave bolts on the conveyor races and against the pair of dogs. Furthermore, when two stave bolts are simultaneously placed on the conveyor in front of one set of dogs it will readily be seen that the runners can incline as required to engage two portions of each stave bolt at leastduring the major portion of their travel through the saws.

After the stave bolts pass from under the hold-down runners they pass on to reserve table conveyor 200, for further operations as'will be hereinafter described.

Because of the success of the automatic equalizer 20, a direct assembly line for the manufacture of rough barrel staves is now possible, that is to say, the three major units of the stave mill can now be aligned in a straight line for a straight through continuous flow of the work piece and furthermore all units of the stave mill are compact enough to be constructed as portable units. This is true even though the other units i.e., the barrel saw 202 and the edger saw 206 in the mill are old.

FIGURE 2 illustrates the general previous arrangement of stave mill units and will sufiice to explain the old method making rough staves from stave bolts which, using the old manual stave bolt equalizer 230, required three or four more persons (indicated in FIGURES 1 and 2 by small circles) to operate the mill than does the new method which utilizes the automatic stave bolt equalizer 20 of the present invention. The old machine grouping utilized a single line shaft 232, driven by a motor 233, having fiat belt takeoifs 234, 235, 236 and 237 to power the manual equalizer 230, the barrel saw 240, dust fan 242, and edger saws 244. Using the old machine arrangement, two men would pick up a stave bolt from a supply table 246, place it on an equalizer slide and manually push the bolt into the twin saws of manual equalizer 230 and then draw the bolt back, remove it from the slide and carry it to the barrel saw reserve table 248. Normally two other men are ready with a second stave bolt to repeat this process. Other operators then proceed to process the sized bolt through the barrel saw 240 and the edger saw 244.

The automatic equalizer 20, FIGURE 1, which has a straight through passage of a stave bolt, permits a new arrangement of machines each of which are self powered and in which one operator feeds the equalizer 20 which passes the sized bolt to a reserve table conveyor 200. One operator receives sized bolts from conveyor 200 and feeds them into the barrel saw 202 from which the curved rough stave is passed to a further conveyor 204 which carries the curved rough staves to the supply table 205 for the rough stave edger saws 206 from which they pass to a grading table 209. Such an arrangement utilizes an aligned machine set-up, as shown diagrammatically in FIGURE 1, and permits the use of a single belt conveyor 208 (see FIGURE 1A) under the aligned machines to carry off waste material whereas the'old method does the steel mesh floor 210 to permit such waste to drop into the waste conveyor 208 to be carried off to a central disposal point. The angled sides 214 of the waste conveyor 208 can be made of sheet material, sloped down to the waste conveyor. belt 208 centered under the machines. Whereas the old'method operates the machines from a line shaft 232 and belts, the new method oper-' ates each machine separately through electric motors. The alignment of machines in the new assembly line method permits increased production with fewer employees, and combined with individual power sources for each machine, permits the mill to be mobile.

Many stave mill owners are confronted with the problem of bringing stave bolts from multiple sources of supply to the mill location and have a problem of relocat- -ing their mills'as the focal points of supply sources change. The new stave bolt equalizer now permits all units of a mill to be made in a manner capable of being moved rapidly and relocated to reduce costs and provide the potential of increased production.

The invention may be embodied and utilized in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiment is therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the fore-' going description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

What is claimed and desired to be secured by United States Letters Patent is:

l. A machine for equalizing lengths of wood work pieces, comprising: substantially vertical yoke supports; a frame; twin, spaced, rotary saws on said frame; conveyor means on said frame including rigid track means passing between said twin saws and moving abutment means cyclically passing along and on said track means for positively engaging and forcing a work piece along said track means substantially perpendicular to the planes of said twin saws; first fastening means, vertically adjustable on said yoke supports, securing said frame on said yoke supports enabling height adjustment of said rotary saws and said conveyor means; elongate brace means; second fastening means, vertically adjustable on said yoke supports above said first fastening means, securing said elongate brace means on said yoke supports above said conveyor means enabling height adjustment of said brace means independent of the height adjustment of said frame; force applying means yieldably supported on said brace means above said conveyor, adapted to slidably engage and force the work piece against said abutment means and against said track means at least during passage through said twin saws; and power means for driving said saws and said conveyor.

2. An equalizing machine as defined in claim 1, wherein said yieldably supported force applying means comprise at least two spaced apart elongate members disposed in the direction of and slightly above said track means; and means are connected to each of said elongate members and are also slidably connected to said brace means enabling independent vertical rise and fall of either and both ends of said elongate members.

3. A machine for equalizing lengths of wood Work pieces, comprising: a frame; twin, spaced, rotary saws on said frame; conveyor means on said frame including rigid track means passing between said twin saws and moving abutment means cyclically passing along and on said track means for positively engaging and forcing a work piece along said track means substantially perpendicular to the planes of said twin saws; power means for driving said saws and said conveyor; force applying means yieldably supported above said conveyor means, adapted to slidably engage and force the work piece against said abutment means and against said track means at least during passage through said twin saws; a portion of said frame comprising elongate brace devices disposed longitudinal above and in the same direction as said track means with each of said brace devices having means providing vertical passage therethrough;- said yieldably supported force applying means comprising at least two spaced apart elongate members disposed in the direction of and slightly above said track means, and means connected to each of said elongate members comprising two substantially vertical members, one pivotally connected 7 adjacent the front end of the associated elongate member and one pivotally connected adjacent the rear end of the associated elongate member and both of said substantially vertical members projecting through a vertical passage in a said brace device and having means secured to the projected end above the brace device adapted to engage the upper part of the brace device and limit the lowermost position of each vertical member; and means connected to the brace device maintaining fore and aft position relative to the brace devices of the portion of said vertical members within said vertical passages.

4. In the combination defined in claim 3, said last named means comprising roller bearings disposed in the passages of said brace devices in front and rear of each of said vertical members.

5.,In the machine combination defined in claim 3, a further portion of said frame comprising means slidably i2 engaging said vertical members to maintainlongitudinal disposition of said elongate members and prevent side- 'ways sway laterally from a position above said tracks.

6. A method of processing rough stave bolts into rough barrel staves along a machine assembly line wherein a straight through operation comprises of steps of: automatic stove bolt equalization by unidirectionally passing rough stave bolts sideways in a confined manner in a straight path; making parallel cuts on both ends of they rough stave bolt during passage along an intermediate portion of the path of movement; automatically convey ing the equalized stave bolt in a path substantially continuous with said straight path to a barrel saw; passing each equalized bolt into the barrel saw and therein cutting the equalized stave into a rough barrel stave with lengthwise curvature; conveying the rough stave from the barrel saw to edging saws in a path substantially continuous with the preceding movements; and processing the rough staves through the edger saws wherein the rough staves are edged to eliminate Waste prior to final processing into barrels.

References Cited in the file of this patent UNITED STATES PATENTS 1,060,793 Seagraves May 6, 1913 2,649,875 Sherman Aug. 25, 1953 2,732,867 May et a1. Jan. 31, 1956 FOREIGN PATENTS 119,480 Sweden Aug. 19, 1947 

